1. Field of the Invention
Embodiments of the present invention relate to a scan driver and a method for driving a display, and an electroluminescent (EL) display including the scan driver. More particularly, embodiments relate to a scan driver and method for driving a display, and an EL display including the scan driver in which a reduced number of clock signals are input to terminals of the scan driver.
2. Description of the Related Art
Generally, a conventional EL display emits light by electrically exciting fluorescent or phosphorescent materials. An organic EL display may drive N×M number of organic EL cells so as to display an image. The organic EL cell may include an anode, e.g., made of a transparent conductive material such as indium tin oxide (ITO), an organic thin film and a cathode, e.g., made of an opaque conductive material, such as metal. The organic thin film may have a multi-layered structure including an emitting layer (EML) for emitting light by combing an electron and a hole, an electron transport layer (ETL) for transporting the electron and a hole transport layer (HTL) for transporting the hole. Further, the organic thin film may include an electron injecting layer (EIL) for injecting the electron and a hole injecting layer (HIL) for injecting the hole.
Driving techniques for the organic EL cell may include a passive matrix (PM) technique and an active matrix (AM) technique. The PM technique refers to a driving technique in which lines of anodes and cathodes orthogonal to each other may be selected to drive light emission cells. The AM technique refers to a driving technique in which each emission cell may be driven by a thin film transistor (TFT) via external signals stored in a capacitor. The AM technique may include a voltage programming technique and a current programming technique according to a signal form applied to maintain a voltage in the capacitor.
Recently, various kinds of light-weight, small-sized light emitting displays have been developed. Organic EL displays may be employed in mobile communication terminals, navigation devices, personal display assistances (PDAs), camcorders, and so forth. For such applications, an organic EL display having a high light emitting efficiency, high luminance, a wide viewing angle, a high resolution, a high response speed and a reduced thickness may be employed. The AM technique may provide better luminance and lower power consumption than the PM technique.
Scan drivers of organic EL displays may employ a latch scan circuit using two clock signals to prevent a scan signal from being changed due to coupling capacitance. The latch scan circuit may have two input terminals for receiving the two clock signals, thereby increasing the size and the manufacturing cost of an integrated circuit (IC) including the latch scan circuit.